I would like to ask about which is the most general/common way to say 'member' in Japanese when talking about a group, organization, association, etc. In particular, is there a word that is "always ok" to use, or does each different type of organization (a school club vs. a research society vs a sports team vs an NPO, for example) use a different term?
会員 and メンバー seem to be the most common words, is that correct? Can they be used interchangeably/in any situation?
I know about 会社員、but I'm interested more in "non company" type of organizations.
Second question: if I want to ask how many members there are in a group/association, do I just use 何名 or is there a specific counter?